1. Field of the Invention
This invention relates to moisture indicating systems, and more particularly to self-contained alarm systems for monitoring the wetness of a floor.
2. Description of the Related Art
Water leaks can cause serious property damage as water collects on a floor. Carpeting, flooring, walls, and furniture can be ruined by water damage due to water leaks. Even leaks of relatively small amounts of water can cause significant damage. In households, these leaks may arise from malfunctions or damage to water heaters, washing machines, and plumbing. Many types of alarm systems have been proposed for detecting leaks of this kind by monitoring the wetness of a floor.
Some alarm systems for monitoring floor moisture include an alarm housing having a bottom surface with a plurality of printed circuit electrodes supported above the floor by support feet. Such alarm systems may include a small remote sensor connected to the housing by a cord. While such alarm systems have great flexibility, they are also of a size that makes them too large and inconvenient for many confined applications, such as under dishwashers or washing machines, and are not as simple to use as more compact systems.
Other alarm systems include a floating housing and support feet extending from the housing, with two separate electrodes on the housing's bottom surface. Although the floating housing increases the survivability of the system, the single pair of electrodes may not have sufficient sensitivity for optimal monitoring.
Finally, other alarm systems may include a moisture sensor comprising a flexible plastic tape with an adhesive backing and a pair of conductive metal strips. The flexible tape is laid out in the area to be monitored for wetness. Although such a detector system provides an extended coverage area, it is not as simple to use as systems comprising a self-contained alarm in a housing, where the alarm is activated and simply placed in the desired location to be monitored.
Thus, there is a need for a floor wetness alarm system that is compact, easy to use, inexpensive, and sensitive to leaks but resistant to false alarms.